Mitsubishi Electric 800 Series Instruction Manual page 211

 PU operation interlock (Pr.79 = "7")
• The operation mode can be forcibly switched to the External operation mode by turning OFF the PU operation interlock
(X12) signal. This function prevents the operation mode from being accidentally unswitched from the PU operation mode.
If the operation mode left unswitched from the PU operation mode, the inverter does not reply to the commands sent
through external commands.
• To input the X12 signal, set "12" in any of Pr.178 to Pr.189 (Input terminal function selection) to assign the function to
a terminal. (For details on Pr.178 to Pr.189, refer to
• Set Pr.79="7" (PU operation interlock).
• If the X12 signal is not assigned, the function of the MRS signal is switched to PU operation internal signal from MRS
(output stop).
X12 (MRS) signal
ON Switching of the operation mode (External, PU, and
NET) is enabled.
Output is stopped during External operation.
OFF Operation mode is forcefully changed to the External
operation mode.
External operation is enabled.
Switching to the PU or NET operation mode from the
External operation mode is disabled.
*1 Depends on the Pr.77 Parameter write selection setting and the writing conditions of each parameter. (Refer to
• Functions/operations by X12 (MRS) signal ON/OFF
Operating status
Operation Status
mode
PU/NET during a
stop
Running
External during a
stop
Running
*1 The mode is switched to the External operation mode regardless of the ON/OFF state of the start signals (STF, STR). Thus, the motor runs under
the External operation mode when the X12 (MRS) signal turns OFF with either of STF or STR in an ON state.
*2 When a fault occurs, the inverter can be reset by pressing
NOTE
• The operation mode cannot switched to the PU operation mode with the start signal (STF, STR) in an ON state even if the
X12 (MRS) signal is ON.
• If the MRS signal is ON and Pr.79 is written to a value other than "7" when the MRS signal is used as the PU interlock
signal during PU operation mode, the MRS signal will act as a regular MRS function (output stop). Also, when Pr.79="7",
the MRS signal becomes the PU interlock signal.
• The logic of the signal follows the Pr.17 MRS input selection setting also when the MRS signal is used as the PU
operation interlock signal. When Pr.17 ="2", ON and OFF in the above explanation are reversed.
• Changing the terminal assignment using Pr.178 to Pr.189 (Input terminal function selection) may affect the other
functions. Set parameters after confirming the function of each terminal.
210
5. PARAMETERS
5.6 (D) Operation command and frequency command
Operation mode
X12 (MRS) signal Operation
mode
*1
ON→OFF External
*1
ON→OFF
OFF→ON
External
ON→OFF
OFF→ON
ON→OFF
page 343.)
Function/Operation
Parameter writing enabled
Writing of parameters other than Pr.79 is disabled.
Operating status
If frequency and start commands are input from
*2
external source, the inverter runs by those
commands.
*2 during a stop
Running→Output shutoff
Output shutoff→Running
on the operation panel.
*1
Parameter writing
page 168.)
Switching to PU
or NET operation
Not available
Not available
Available
Not available
Not available
Not available
mode